1. Field of the Invention
The present invention relates to the field of deployable systems and mooring systems, and more particularly, to the field of deployable autonomous mooring systems.
2. Description of the Related Art
In the last decade, interest in the ocean has shifted from the deep ocean to the littoral regions of the world. This change has been driven by the need to successfully operate in the complex littoral oceans that are characterized by intricate bottom topography, changes in water properties and time and spatially varying currents. The coupled effects of these characteristics create a complex environment for optical and acoustical transmission, vessel and AUV (autonomous underwater vehicle) operation, remote sensing as well as many other operations. Moored ocean buoys are an excellent platform to make coastal measurements to assess the littoral environment and to mount communication and positioning systems.
Although moorings are a proven technology, they have been developed for ship deployment with a focus on long term operation, access to large vessels and a large supply of energy. Thus, such systems are usually large; they have a large surface signature and require a surface vessel for deployment and servicing. The deployment, use and maintenance of such systems is impractical in a hostile theater far from the United States, where rapid deployment, low observability and autonomous operation are essential.
Air deployment provides a more rapid and less risky alternative to ship based deployment of moorings in hostile theaters. The “A”-sized form factor, 0.12 m (4.875 in) in diameter and 0.9 m (36 in) in length, is the standardized Navy dimension for rapidly deployable systems. The A-sized standard is adopted for many buoys used in ocean monitoring that are deployed from aircraft, helicopters, ships and submarines using pressure and gravity launch tubes, as well as charge-activated devices. However, an effective self-mooring system does not exist for an A-sized deployable system. Hence, the systems are typically left un-moored when they are deployed. In consequence, the systems may drift with ocean currents, tending to move ashore or out of the area of active interest. Accordingly, deployment of new systems is frequently required, leading to higher operating costs, and higher risks to Navy assets and personnel.
Although some deployable moorings do exist, they often exceed the “A”-sized dimensional standard. For example, a large deep-water oceanographic sensor system has been developed which has a length of 3.3 m, a diameter of 0.71 m diameter, and weighs 1100 kg. L. W. Bonde, et al., Air Deployed Oceanographic Mooring—AB1034, Proceedings Oceans 1993, vol. 1 at 237–50, 1993. Further, parachute entanglement is a common problem arising when mooring systems are air deployed. In particular, the parachute trails the system on a thin line. Upon air-sea penetration, the parachute may fall over the system, obstructing the deployment of sensors.
A recent air-deployable “A”-sized sonobuoy which includes an anchor that has been developed is the SSQ-57M, produced by Sparton Electronics of Deleon Springs, Fla. The sonobuoy is 0.57 m long and weighs 9.3 kg, and is intended for detecting underwater acoustical energy radiated by surface or subsurface vessels in shallow water. This system, however, is limited to a very short time of operation and deploys a fixed amount of mooring line.
Accordingly, the prior art solutions offer one or more problems with the different aspects of the device. In some instances, for a device deployed from the air, the parachute may interfere with the device upon deployment in the water. In other devices, the mooring line may not deploy properly, or this is an insufficient amount of line or an excess of line, thereby preventing the device from being properly moored. Also, in still other devices, the device may not be sized correctly to permit deployment from air, water and/or land. In yet other devices, the module may not be deployed correctly such that it may be used after deployment and/or may have to be replaced after a short period of time due to a short operating life. Also, in still other devices, the anchor may only work well in specific bottom types. In still other devices, the buoy may be forced under the water surface due to the design of the buoy and the strength of the current, thereby eliminating the advantage of using the module.
As such, what is needed is a deployable and autonomous mooring device that solves one or more of these problems. Additionally, what is needed is a device that incorporates one or more features such that the device may be used in a wide variety of locations and/or to deploy a wide variety of modules in an effective and dependable manner.